1. Field of the Invention
The present invention relates to: a method of producing a print product, for example, a newspaper or the like, the method performing digital printing on a continuous paper, cutting the continuous paper into paper sheets, and folding and gathering the paper sheets after cutting to produce the print product; and a print product production device.
2. Description of the Related Art
Print products represented by newspapers, commercial printed matter, and the like, have fulfilled their mission by using plates to print items of identical content in large quantities, and by these items being transferred or distributed for profit or free of charge.
However, in recent years, in commercial printing, for example, there has been an increasing requirement for print products of individually differing content, such as personalized direct mail or pamphlets directed to customers of limited district, generation, occupation, etc., and for print products produced in extremely small quantities. Similarly, in newspapers as a representative medium of mass communication, there has also been a shift in demand from newspapers covering various fields including politics, economy, literature, sports, hobby, entertainment, etc., to newspapers that match particular tastes of readers, such as a newspaper focusing on topics field by field, a newspaper targeting readers of a limited district, generation, occupation, etc., a newspaper having characters of both of these, etc. Accordingly, a method of producing a print product and a print product production device to deal with these demands are proposed by Patent Documents 1 to 4 identified below. Note that the print product involved in each of Patent Documents 1 to 4 is a newspaper.
A method of producing a print product disclosed in Patent Document 1 includes (1) a receiving element such as a grasping device, a sucker, etc. receiving sheet by sheet, from a conveyor, sheets of paper on which digital printing such as ink jet printing, etc. has been performed or sheets of paper cut out from a continuous paper on which digital printing has been performed, and carrying the sheets sequentially into a collecting station, (2) stacking the sheets one upon another in the collecting station, (3) discharging a stack of a certain number of sheets from the collecting station, (4) continuously carrying a subsequent series of printed sheets one by one into the collecting station from which the stack has been discharged, (5) carrying the stack discharged from the collecting station into a folding station, and (6) folding the stack in the folding station and outputting the stack from the folding station. The steps (1) to (6) are performed sequentially by the respective stations.
A method of producing a print product disclosed in Patent Document 2 is approximately the same as that disclosed in Patent Document 1. To be specific, Patent Document 2 is different from Patent Document 1 in disclosing that after a printed continuous paper is dried, it is divided into two pieces in parallel with the continuity direction, and in disclosing as to the steps (1) and (2) that a delivery fan mechanism which rotates intermittently is provided in the collecting station, and sheets of paper cut out from a continuous paper on which digital printing has been performed are discharged toward the blades of the delivery fan maintained horizontally so that the sheets are stacked, or that sheets of paper cut out from a continuous paper on which digital printing has been performed are sequentially inserted into between respective blades of a delivery fan having many blades arranged in a circumferential direction, and then a stripper shoe lets the sheets of paper fall from between the blades onto a conveyor so that the sheets are stacked.
A method of producing a print product disclosed in Patent Document 3 includes, in an order from an upstream side: a digital printing system which prints on continuous paper; a side edge cutting station which cuts unnecessary side edge portions of the continuous paper; a lengthwise direction cutting station which cuts the continuous paper in its lengthwise direction (in parallel with the continuity direction); a widthwise cutting station which cuts the continuous paper widthwise (orthogonally to the continuity direction) to separate it into sheets of paper; a removing device which removes faulty sheets including a poorly printed portion or a damaged portion, etc from the separated sheets on the process path; a collecting station in which the sheets of paper are stacked; a carrying device which carries the stack of sheets stacked in the collecting station to a widthwise folding station; a widthwise folding station which folds the stack carried by the carrying device in a direction transverse to the carrying direction; a lengthwise direction folding station which folds the stack in the carrying direction; a sewing station which sews the folded stack along the folding edge; a second collecting station into which a signature formed by folding the stack or by folding and sewing the stack is inserted one into another; and a delivery station which delivers a completed print product. By bringing any stations that are unnecessary according to the configuration and format of the print product to be made into a non-operative condition, it is possible to produce various types of print products that are different from one another in the configuration and format, without interrupting the continuous producing process.
By indicating the laid-open publication number of a European Patent, Patent Document 3 suggests, as the collecting station, a rotary cylinder mechanism which is provided with plural pairs of claws arranged in parallel with its shaft center and which allows sheets of paper to be stacked on its outer circumferential surface by the two claws of each pair alternately sandwiching and retaining a sheet between themselves and the outer circumferential surface. Likewise, by indicating the laid open publication number of a European Patent, Patent Document 3 suggests, as either or both of the widthwise folding station and the lengthwise direction folding station, a mechanism which includes at least: a feed surface; a pair of initial folding rollers parallel with the feed surface and having axes parallel with each other; at least one pair of moving rollers having axes orthogonal to the feed surface and provided above the initial folding rollers; and a rectilinear knife which is a folding blade provided in parallel with the axes of the initial folding rollers. This mechanism feeds a stack of sheets, which are horizontally put and fed to the feed surface, into between the pair of initial folding rollers by causing the rectilinear knife to project upward a portion of the stack at which the stack is to be folded, then causes the two initial folding rollers to rotate about their axes while sandwiching therebetween the projected stack of sheets to form an incomplete folding line and at the same time send forth the stack to the at least one pair of moving rollers provided above, and then causes the at least one pair of moving rollers to rotate while sandwiching therebetween the folding line to form a complete folding line and at the same time send forth the stack of sheets in parallel with the axes of the initial folding rollers.
When a print product is a newspaper of a blanket size, a method of producing a print product disclosed in Patent Document 4 defines a blanket-size newspaper such that the widthwise direction of the newspaper is made parallel to the widthwise direction of a continuous paper and two pages are aligned in the widthwise direction of the continuous paper, prints repeatedly a predetermined number of the blanket-size newspaper pages lined in the continuity direction of the continuous paper by a digital printing device, sends forth the continuous paper to the downstream side and at the same time cuts the continuous paper in parallel with the widthwise direction of the continuous paper in alignment with the printed newspaper page in a length dimension of the blanket-size newspaper, scores the cut sheets at their widthwise center, moreover, stacks the scored sheets by making the sheets sequentially straddle a collation chain such that their scored folding line aligns with the spine of the collation chain, folds the sheets into two by causing a discharging member to project the folding line of the plurality of sheets straddling the collation chain while being stacked into between carrying conveyors facing each other, and guides the twofold sheets to a quarter folding mechanism, which then produces the sheets into a fourfold blanket-size newspaper. When a print product is a newspaper of a tabloid size which is half the blanket size, a method for producing a print product disclosed in Patent Document 4 defines a newspaper of a tabloid size such that the lengthwise direction of the newspaper is made parallel to the widthwise direction of a continuous paper and two pages are aligned in the continuity direction of the continuous paper, sends forth to the downstream side the continuous paper on which a predetermined number of the tabloid-size newspaper pages are printed repeatedly lined in the continuity direction of the continuous paper by the digital printing device with two pages of the newspaper arranged in the widthwise direction of the continuous paper and at the same time cuts the continuous paper in parallel with the widthwise direction of the continuous paper in alignment with the printed newspaper page at lengths double the width dimension of the tabloid-size newspaper, scores the cut sheets at their widthwise center, stacks the scored sheets by making the sheets sequentially straddle the collation chain such that their scored folding line aligns with the spine of the collation chain, folds the sheets into two by causing the discharging member to project the folding line of the plurality of sheets straddling the collation chain while being stacked into between the carrying conveyors facing each other, guides the twofold sheets to a cutting/sewing station, cuts the twofold sheets at the vicinity of the scored folding line along the folding line to produce them into a stack of cut sheets in each of which there are arranged two pages of the tabloid-size newspaper of which width direction is parallel with the cutting edge, and if necessary, sews the stack at its center in the direction in which the two pages of the newspaper are arranged such that the stack is sewn along a direction orthogonal to the cutting edge, then guides the stack to the quarter folding mechanism, which quarter-folds the stack at its center in the alignment direction of two pages of the newspaper along the direction orthogonal to the cutting edge to produce it into a twofold tabloid-size newspaper.
In other words, Patent Document 4 discloses a method of producing a fourfold print product having a print surface aligned with a width dimension of a continuous paper, and a method of producing a twofold print product having a print surface aligned with a dimension which is half of a width dimension of a continuous paper.    [Patent Document 1] JP 2002-193545 A    [Patent Document 2] JP 2003-341927 A    [Patent Document 3] JP 2007-15859 A    [Patent Document 4] JP 2007-76923 A